//===-- Value.cpp - Implement the Value class -----------------------------===//
//
-// This file implements the Value class.
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the Value and User classes.
//
//===----------------------------------------------------------------------===//
-#include "llvm/ValueHolderImpl.h"
+#include "llvm/Constant.h"
+#include "llvm/DerivedTypes.h"
#include "llvm/InstrTypes.h"
-#include "llvm/SymbolTable.h"
-#include "llvm/SymTabValue.h"
-#include "llvm/ConstantPool.h"
-#include "llvm/ConstPoolVals.h"
-#include "llvm/Type.h"
-#ifndef NDEBUG // Only in -g mode...
-#include "llvm/Assembly/Writer.h"
-#endif
+#include "llvm/Module.h"
+#include "llvm/ValueSymbolTable.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/LeakDetector.h"
#include <algorithm>
+using namespace llvm;
//===----------------------------------------------------------------------===//
// Value Class
//===----------------------------------------------------------------------===//
-Value::Value(const Type *ty, ValueTy vty, const string &name = "") : Name(name){
- Ty = ty;
- VTy = vty;
+static inline const Type *checkType(const Type *Ty) {
+ assert(Ty && "Value defined with a null type: Error!");
+ return Ty;
+}
+
+Value::Value(const Type *ty, unsigned scid)
+ : SubclassID(scid), SubclassData(0), Ty(checkType(ty)),
+ UseList(0), Name(0) {
+ if (!isa<Constant>(this) && !isa<BasicBlock>(this))
+ assert((Ty->isFirstClassType() || Ty == Type::VoidTy ||
+ isa<OpaqueType>(ty)) &&
+ "Cannot create non-first-class values except for constants!");
}
Value::~Value() {
// Check to make sure that there are no uses of this value that are still
// around when the value is destroyed. If there are, then we have a dangling
// reference and something is wrong. This code is here to print out what is
- // still being referenced. The value in question should be printed as
+ // still being referenced. The value in question should be printed as
// a <badref>
//
- if (Uses.begin() != Uses.end()) {
- for (use_const_iterator I = Uses.begin(); I != Uses.end(); ++I)
- cerr << "Use still stuck around after Def is destroyed:" << *I << endl;
+ if (!use_empty()) {
+ DOUT << "While deleting: " << *Ty << " %" << Name << "\n";
+ for (use_iterator I = use_begin(), E = use_end(); I != E; ++I)
+ DOUT << "Use still stuck around after Def is destroyed:"
+ << **I << "\n";
}
#endif
- assert(Uses.begin() == Uses.end());
+ assert(use_empty() && "Uses remain when a value is destroyed!");
+
+ // If this value is named, destroy the name. This should not be in a symtab
+ // at this point.
+ if (Name)
+ Name->Destroy();
+
+ // There should be no uses of this object anymore, remove it.
+ LeakDetector::removeGarbageObject(this);
}
-void Value::replaceAllUsesWith(Value *D) {
- assert(D && "Value::replaceAllUsesWith(<null>) is invalid!");
- assert(D != this && "V->replaceAllUsesWith(V) is NOT valid!");
- while (!Uses.empty()) {
- User *Use = Uses.front();
-#ifndef NDEBUG
- unsigned NumUses = Uses.size();
-#endif
- Use->replaceUsesOfWith(this, D);
+/// hasNUses - Return true if this Value has exactly N users.
+///
+bool Value::hasNUses(unsigned N) const {
+ use_const_iterator UI = use_begin(), E = use_end();
-#ifndef NDEBUG // only in -g mode...
- if (Uses.size() == NumUses)
- cerr << "Use: " << Use << "replace with: " << D;
-#endif
- assert(Uses.size() != NumUses && "Didn't remove definition!");
- }
+ for (; N; --N, ++UI)
+ if (UI == E) return false; // Too few.
+ return UI == E;
}
-void Value::killUse(User *i) {
- if (i == 0) return;
- use_iterator I = find(Uses.begin(), Uses.end(), i);
+/// hasNUsesOrMore - Return true if this value has N users or more. This is
+/// logically equivalent to getNumUses() >= N.
+///
+bool Value::hasNUsesOrMore(unsigned N) const {
+ use_const_iterator UI = use_begin(), E = use_end();
- assert(I != Uses.end() && "Use not in uses list!!");
- Uses.erase(I);
-}
+ for (; N; --N, ++UI)
+ if (UI == E) return false; // Too few.
-User *Value::use_remove(use_iterator &I) {
- assert(I != Uses.end() && "Trying to remove the end of the use list!!!");
- User *i = *I;
- I = Uses.erase(I);
- return i;
+ return true;
}
-//===----------------------------------------------------------------------===//
-// User Class
-//===----------------------------------------------------------------------===//
+/// getNumUses - This method computes the number of uses of this Value. This
+/// is a linear time operation. Use hasOneUse or hasNUses to check for specific
+/// values.
+unsigned Value::getNumUses() const {
+ return (unsigned)std::distance(use_begin(), use_end());
+}
-User::User(const Type *Ty, ValueTy vty, const string &name)
- : Value(Ty, vty, name) {
+static bool getSymTab(Value *V, ValueSymbolTable *&ST) {
+ ST = 0;
+ if (Instruction *I = dyn_cast<Instruction>(V)) {
+ if (BasicBlock *P = I->getParent())
+ if (Function *PP = P->getParent())
+ ST = &PP->getValueSymbolTable();
+ } else if (BasicBlock *BB = dyn_cast<BasicBlock>(V)) {
+ if (Function *P = BB->getParent())
+ ST = &P->getValueSymbolTable();
+ } else if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
+ if (Module *P = GV->getParent())
+ ST = &P->getValueSymbolTable();
+ } else if (Argument *A = dyn_cast<Argument>(V)) {
+ if (Function *P = A->getParent())
+ ST = &P->getValueSymbolTable();
+ } else {
+ assert(isa<Constant>(V) && "Unknown value type!");
+ return true; // no name is setable for this.
+ }
+ return false;
}
-// replaceUsesOfWith - Replaces all references to the "From" definition with
-// references to the "To" definition.
-//
-void User::replaceUsesOfWith(Value *From, Value *To) {
- if (From == To) return; // Duh what?
+/// getNameStart - Return a pointer to a null terminated string for this name.
+/// Note that names can have null characters within the string as well as at
+/// their end. This always returns a non-null pointer.
+const char *Value::getNameStart() const {
+ if (Name == 0) return "";
+ return Name->getKeyData();
+}
- for (unsigned OpNum = 0; Value *D = getOperand(OpNum); ++OpNum) {
- if (D == From) { // Okay, this operand is pointing to our fake def.
- // The side effects of this setOperand call include linking to
- // "To", adding "this" to the uses list of To, and
- // most importantly, removing "this" from the use list of "From".
- setOperand(OpNum, To); // Fix it now...
- }
- }
+/// getNameLen - Return the length of the string, correctly handling nul
+/// characters embedded into them.
+unsigned Value::getNameLen() const {
+ return Name ? Name->getKeyLength() : 0;
}
-//===----------------------------------------------------------------------===//
-// SymTabValue Class
-//===----------------------------------------------------------------------===//
+std::string Value::getNameStr() const {
+ if (Name == 0) return "";
+ return std::string(Name->getKeyData(),
+ Name->getKeyData()+Name->getKeyLength());
+}
-// Instantiate Templates - This ugliness is the price we have to pay
-// for having a ValueHolderImpl.h file seperate from ValueHolder.h! :(
-//
-template class ValueHolder<ConstPoolVal, SymTabValue>;
+void Value::setName(const std::string &name) {
+ setName(&name[0], name.size());
+}
-SymTabValue::SymTabValue(const Type *Ty, ValueTy dty, const string &name = "")
- : Value(Ty, dty, name), ConstPool(this) {
- ParentSymTab = SymTab = 0;
+void Value::setName(const char *Name) {
+ setName(Name, Name ? strlen(Name) : 0);
}
+void Value::setName(const char *NameStr, unsigned NameLen) {
+ if (NameLen == 0 && !hasName()) return;
+ assert(getType() != Type::VoidTy && "Cannot assign a name to void values!");
+
+ // Get the symbol table to update for this object.
+ ValueSymbolTable *ST;
+ if (getSymTab(this, ST))
+ return; // Cannot set a name on this value (e.g. constant).
+
+ if (!ST) { // No symbol table to update? Just do the change.
+ if (NameLen == 0) {
+ // Free the name for this value.
+ Name->Destroy();
+ Name = 0;
+ return;
+ }
+
+ if (Name) {
+ // Name isn't changing?
+ if (NameLen == Name->getKeyLength() &&
+ !memcmp(Name->getKeyData(), NameStr, NameLen))
+ return;
+ Name->Destroy();
+ }
+
+ // NOTE: Could optimize for the case the name is shrinking to not deallocate
+ // then reallocated.
+
+ // Create the new name.
+ Name = ValueName::Create(NameStr, NameStr+NameLen);
+ Name->setValue(this);
+ return;
+ }
+
+ // NOTE: Could optimize for the case the name is shrinking to not deallocate
+ // then reallocated.
+ if (hasName()) {
+ // Name isn't changing?
+ if (NameLen == Name->getKeyLength() &&
+ !memcmp(Name->getKeyData(), NameStr, NameLen))
+ return;
+
+ // Remove old name.
+ ST->removeValueName(Name);
+ Name->Destroy();
+ Name = 0;
+
+ if (NameLen == 0)
+ return;
+ }
+
+ // Name is changing to something new.
+ Name = ST->createValueName(NameStr, NameLen, this);
+}
-SymTabValue::~SymTabValue() {
- ConstPool.dropAllReferences();
- ConstPool.delete_all();
- ConstPool.setParent(0);
- delete SymTab;
+/// takeName - transfer the name from V to this value, setting V's name to
+/// empty. It is an error to call V->takeName(V).
+void Value::takeName(Value *V) {
+ ValueSymbolTable *ST = 0;
+ // If this value has a name, drop it.
+ if (hasName()) {
+ // Get the symtab this is in.
+ if (getSymTab(this, ST)) {
+ // We can't set a name on this value, but we need to clear V's name if
+ // it has one.
+ if (V->hasName()) V->setName(0, 0);
+ return; // Cannot set a name on this value (e.g. constant).
+ }
+
+ // Remove old name.
+ if (ST)
+ ST->removeValueName(Name);
+ Name->Destroy();
+ Name = 0;
+ }
+
+ // Now we know that this has no name.
+
+ // If V has no name either, we're done.
+ if (!V->hasName()) return;
+
+ // Get this's symtab if we didn't before.
+ if (!ST) {
+ if (getSymTab(this, ST)) {
+ // Clear V's name.
+ V->setName(0, 0);
+ return; // Cannot set a name on this value (e.g. constant).
+ }
+ }
+
+ // Get V's ST, this should always succed, because V has a name.
+ ValueSymbolTable *VST;
+ bool Failure = getSymTab(V, VST);
+ assert(!Failure && "V has a name, so it should have a ST!");
+
+ // If these values are both in the same symtab, we can do this very fast.
+ // This works even if both values have no symtab yet.
+ if (ST == VST) {
+ // Take the name!
+ Name = V->Name;
+ V->Name = 0;
+ Name->setValue(this);
+ return;
+ }
+
+ // Otherwise, things are slightly more complex. Remove V's name from VST and
+ // then reinsert it into ST.
+
+ if (VST)
+ VST->removeValueName(V->Name);
+ Name = V->Name;
+ V->Name = 0;
+ Name->setValue(this);
+
+ if (ST)
+ ST->reinsertValue(this);
}
-void SymTabValue::setParentSymTab(SymbolTable *ST) {
- ParentSymTab = ST;
- if (SymTab)
- SymTab->setParentSymTab(ST);
+
+// uncheckedReplaceAllUsesWith - This is exactly the same as replaceAllUsesWith,
+// except that it doesn't have all of the asserts. The asserts fail because we
+// are half-way done resolving types, which causes some types to exist as two
+// different Type*'s at the same time. This is a sledgehammer to work around
+// this problem.
+//
+void Value::uncheckedReplaceAllUsesWith(Value *New) {
+ while (!use_empty()) {
+ Use &U = *UseList;
+ // Must handle Constants specially, we cannot call replaceUsesOfWith on a
+ // constant because they are uniqued.
+ if (Constant *C = dyn_cast<Constant>(U.getUser())) {
+ if (!isa<GlobalValue>(C)) {
+ C->replaceUsesOfWithOnConstant(this, New, &U);
+ continue;
+ }
+ }
+
+ U.set(New);
+ }
}
-SymbolTable *SymTabValue::getSymbolTableSure() {
- if (!SymTab) SymTab = new SymbolTable(ParentSymTab);
- return SymTab;
+void Value::replaceAllUsesWith(Value *New) {
+ assert(New && "Value::replaceAllUsesWith(<null>) is invalid!");
+ assert(New != this && "this->replaceAllUsesWith(this) is NOT valid!");
+ assert(New->getType() == getType() &&
+ "replaceAllUses of value with new value of different type!");
+
+ uncheckedReplaceAllUsesWith(New);
}
-// hasSymbolTable() - Returns true if there is a symbol table allocated to
-// this object AND if there is at least one name in it!
+//===----------------------------------------------------------------------===//
+// User Class
+//===----------------------------------------------------------------------===//
+
+// replaceUsesOfWith - Replaces all references to the "From" definition with
+// references to the "To" definition.
//
-bool SymTabValue::hasSymbolTable() const {
- if (!SymTab) return false;
+void User::replaceUsesOfWith(Value *From, Value *To) {
+ if (From == To) return; // Duh what?
- for (SymbolTable::const_iterator I = SymTab->begin();
- I != SymTab->end(); ++I) {
- if (I->second.begin() != I->second.end())
- return true; // Found nonempty type plane!
- }
-
- return false;
+ assert(!isa<Constant>(this) || isa<GlobalValue>(this) &&
+ "Cannot call User::replaceUsesofWith on a constant!");
+
+ for (unsigned i = 0, E = getNumOperands(); i != E; ++i)
+ if (getOperand(i) == From) { // Is This operand is pointing to oldval?
+ // The side effects of this setOperand call include linking to
+ // "To", adding "this" to the uses list of To, and
+ // most importantly, removing "this" from the use list of "From".
+ setOperand(i, To); // Fix it now...
+ }
}
+